Certain thiamine disulfide compounds

ABSTRACT

Thiamine disulfide compounds represented by the formula:   WHEREIN R represents an alkylthio group containing 1 to 4 carbon atoms or an alkylsulfinyl group containing 1 to 4 carbon atoms, being useful as anti-coccidial agents for poultry, are prepared by two routes.

llnited States Patent Takamizawa et al.

[ 51 Mar. 18, 1975 CERTAIN THIAMINE DISULFIDE COMPOUNDS [75] Inventors: Akira Takamizawa, Osaka; Kentaro Hirai, Kyoto; Hiroshi ()ikawa, Kusatsu; Kunihei lnazu, Suita, all of Japan [73] Assignee: Shionogi & Co., Ltd., Osaka, Japan [22] Filed: Sept. 26, 1972 [2!] Appl. No; 292,454

UNITED STATES PATENTS 3,734,9[3 5/1973 Takamizawa ct al. 260/2565 B FOREIGN PATENTS OR APPLICATIONS 4321736 9/1968 Japan 260/2565 B Primary E.\'aminer-R. Gallagher Attorney, Agent, or Firm-Wender0th, Lind & Ponack [57] ABSTRACT Thiamine disulfide compounds represented by the formula:

N l cit C-CH2-N /s N H ==C\ c11 cn cn n 2 wherein R represents an alkylthio group containing 1 to 4 carbon atoms or an alkylsulfinyl group containing 1 to 4 carbon atoms, being useful as anticoccidial agents for poultry, are prepared by two routes.

3 Claims, N0 Drawings CERTAIN THIAMINE DISULFIDE COMPOUNDS coc'cidial agents. A further object of the invention is to embody a process for preparing the thiamine disulfide The present mvemlon {Flaws to thlamme dlsulilde compounds (l),and their acid-addition salts. These and p l production f q M pamcu' other objects will be apparent to those conversant with lady mvemlon relates to thlamme dlsulfide 5 the art to which the present invention pertains from the pounds and their acid-addition salts, having antifollowing description coccldial activity for poultry, and their production. The said thiamine (Sulfide Compounds (I) can be The said thiamine disulfide compounds are reprcre arcd by the following two routes. Route A sented by the formula: p p i 2 cao E ca c c-ca N g S (I) 3 ll 2 N CH CH2? 2 N C-NH 2 ca l s 3 z S X Thi 12/ ll ll c c CH H CH ca R CHZCHZR 2 r 3 2 2 (II) (1) Route B N=CNH 2 cu l l *f ca c C-CH2N s .1: (Ha) II II o cu ca ca -s-a S i s Thia Thia/ o 1 1 cu ca s-n 2 ca ca s-a 2 wherein R represents an alkylthio group containing 1 55 wherein X represents an acid residue (e.g., a residue of to 4 carbon atoms (e.g., methylthio, ethylthio, nan inorganic acid, including hydrochloric acid, sulfuric butylthio) or an alkylsulfinyl group containing 1 to 4 acid, nitric acid, thiocyanic acid and phosphoric acid; carbon atoms (e.g., methylsulfinyl, cthylsulfinyl, isoor a residue of an organic acid, including succinic acid,

propylsulfinyl). (The partial formula encompassed by benzoic acid, benzenesulfonic acid, naphthalenesulthe dotted line in the above formula will be hereinafter 6Q fonic acids, tartaric acid, and acetic acid), R repreabbreviated as Thia.) sents an alkyl group containing 1 to 4 carbon atoms Accordingly, it is a basic object of the present inven- (e.g., methyl, ethyl, isopropyl, sec-butyl), and R is as tion to embody the thiamine disulfide compounds (I), defined above.

and their acid-addition salts. Another object of this in- Route A:

vention is to embody the thiamine disulfide compounds 5 The starting thiazolium salt (II) can be prepared, for (l), and their acid-addition salts being useful as antiexample, by reacting the 2 methyl-4-amino-5- 3 4 halogenomethylpyrimidine with the 4-methyl-5-(2- can be effected in a conventional manner such as trcatalkylthioethyl)-thiazole to give thethiazolium salt (llb) ing the thiamine disulfide compound (I) with an acid in and oxidizing said thiazolium salt (Ilb), as shown in the an appropriate solvent. Examples of the pharmaceutifollowing Schemei cally acceptable acid-addition salts are hydrochloride.

CH C CCH N S .X Oxldatlon IIa N on 1 CH CH CH S-R wherein Y represents a halogen atom (e.g., chlorine, hydrobromide, hydroiodide, sulfate, nitrate, phosbromine, iodine), and R and X each is as defined phate, thiocyanate, oxalate, succinate, and naphtha] above [Takamizawa, et 21].: Belgian Pat. No. 757,947]. enedisulfonates. This route is carried out by oxidizing the thiazolium salt Thus obtained thiamine disulfide compounds (I) or (ll) in the presence of a base (e.g., sodium hydroxide, their acid-addition salts are useful as an anti-coccidial potassium hydroxide, sodium ethoxide, lithium carbonagent in prophylaxis and/or therapy. Avian coccidiosis ate,calcium hydroxide) in an amount at least sufficient due to Eimeria tenella, Eimeria necalrix, or Eimeria to afford the alkali or alkali earth thiolate in the presacervulina induces lesions in the digestive organs, genence of an inert solvent (e.g., water, a mixture of water eral prostration death and growth inhibition in poultry with methanol, ethanol, chloroform, or methylene such as chicks, turkeys, or ducks. Compounds heretochloride') with or without cooling or heating. Examples fore used as anti-coccidial agents include sulfa drugs, of the oxidizing agent are potassium ferricyanate, ionitrofurans, quinolines, anti-thiamine agents, benzadine-potassium iodide, hydrogen peroxide, air in the mides and antibiotic substances. These known antipresence of a ferrous ion, and other conventional oxicoccidial agents suffer from some drawbacks in their dizing agents for convertingathiol into the correspond- 40 degree of the anti-coccidial activity, their toxicity to ing disulfide. These oxidizing agents may be used in a the hosts and the emergence of strains having drug reconventional manner. sistance owing to misuse of the drugs over a long pe- Route B: riod. Such factors have gradually decreased the value The starting thiazolium salt (Ila) is prepared in the of the known drugs. Advantages of the present invenabove mentioned preparation of said thiazolium salt tion consist in that the thiamine disulfide compounds (II). This route is carried out by treating the thiazolium (l) or their acid-addition salts have low toxicity to host salt (Ila) with a base (e.g., sodium hydroxide, potaspoultry, and the said compounds (I) or their acidsium hydroxide, calcium hydroxide, lithium carbonate, addition salts show very powerful anti-coccidial activity potassium bicarbonate, sodium ethoxide) in an amount for both prophylaxis and treatment of the disease. sufficient to afford the thiol but not to exceed in an For anti-coccidial compositions, comprising the said inert solvent (e.g., water, a mixture of water with meththiamine disulfide compounds (I) or their acid-addition anol, ethanol, chloroform, dimethylsulfoxide, dimethsalts, suitable preparations which may be used, include: ylformamide, or methylene chloride) at room temperapowders, granules, solutions, dispersions, premixes, ture or with heating. This reaction can proceed also in capsules, emulsions, tablets, etc. These compounds a solid diluent (e.g., glucose, lactose, starch). This r emay be used singly or in combination with an appropriaction is considered to proceed via the intermediate ate carrier ordinarily used in this field. There can be represented by the following formula: combined ordinarily additives, vehicles, disintegrating S S Thia i} Thia,

CH CH S-R R -S-CH CH Thus btained hiam ne sulf e COmPOUHdS -fiagents, lubricants, and coating materials. In general, a m y. h n req ired. be converted into acidsuitable concentration of the thiamine disulfide comaddition salts suitable for pharmaceutical use, having pounds (I) or their acid-addition salts for poultry feed low toxicity and desirable stability. Such a conversion is at least 0.003 weight percent. For prophylactic use,

tion, suspension or emulsion may be added to drinking water; capsules or tablets may be administered orally as they are. By the carrier is meant a diluent to be ordinarily added into poultry feed and involves illustratively water, lactose, sucrose, talc, pectin, wheat powder, rice bran, wheat bran, corn powder, soy bean meal, crushed grain powder, and the like. The present anti-coccidial compositions may be optionally used in combination with animal drugs including antibiotics, other known anti-coccidial agents and anthelmintics.

The practical effects of the anti-coccidial agents of this invention are shown by the following experiments.

a. Test Method:

Several groups of test animals, each group consisting of five White Leghorn chicks were orally infected with 50,000 sporulated oocysts of Eimeria tenella per chick. Test animals were given with feed containing test compounds for 8 days after infection. On the 8th day, test animals were anatomized, and cecal lesions were ob served. During the period of administration of the test compound, the number of the hematochezia, ratio of survival, relative weight gain, number of oocysts and cecal lesion score were determined.

b. Test Compound:

When anti-coccidial activity against Et'meria neeatrix was examined in the same manner as above, the present thiamine disulfide compounds (Compound No. 2 and Compound No. 3) were completely prophylactic in a concentration of 0.02 percent in the feed and effective in a concentration of 0.005 percent in the feed. Still. Compound No. 3 was effective against Eimeriu 0C8!" vulina in a concentration of 0.08 percent in the feed.

Acute toxicity of the present thiamine disulfide com- 10 pounds (Compound No. 2 and Compound No. 3) was examined by intraperitoneal administration in an aque ous suspension of the test compound to chicks. and the results of the acute toxicity test are shown in Table 2.

Clearly, as shown in the above results on the prophylaxis and treatment for avian coccidiosis, the thiamine Note 3-( 2-Methyl-4-aminopyrimidirrS-ylntethyl l 4-mcthyl-5-( Z-sulfoethyl )thiazoliunt chloride hydrate Bis- {2-[ N-( 2-methyl-4-aminopyrimidin-S ylmethyl )formamido ll Zmtethylsullinylethyl)-l-propenyl} disulfide Control Subject matter of this invention Subject matter of this invention c. Results:

disulfide compounds (Compound No. 2 and Com- The results of the test against cecal coccidiosis in pound No. 3) show anti-coccidial activity superior to White Leghorn chicks are shown in Table 1.

that of the analogous 2-sulfoethylthiazolium salt (Com- Table 1 Concn. Total of Survival Relative Number Cecal Com (7!) in hematoratio weight of lesion pound feed chezia* ('7!) gain (/1) oocyst score No. t i (OPG HM 0.0l 52 81 l.6X|0" 0.02 0 I00 I26 0 0 2 0.0] 0 I00 100 l.2 l0

0.005 5 100 96 .9Xl0" ll 0.0025 2800 100 89 l 5 l0' 0.02 0 l00 l l l 0 3 0.0 l 0 100 I24 0 I 0.005 9 100 102 2.8 I0- 6 0.0025 2800 I00 102 2.0 l0 IX Control (a) 2800 2] 6.3Xl0 20 (b) 0 I00 0 *1 shows the total count of hematochezia per 5 chicks and shows tlte ratio of the iner sed body weight of c shows tlte count of oocysls existing per gram ollet I shows the degree ol pathological change in cccunt. Survival chicks were anaton were observed macroscopically. Degrees of pathological change in cecum were c 00 shows that too many counts were observed.

-i treated groups orinlected control group to that olchicks in uninfected control group.

s which is abbreviated as ().P.(i.

tized on the 8th day after infection and degrees ol'pathological change in cccttnt lass 'cd into 5 orders from 0 to 4 tserions 4. considerable. 3; moderate, 2; slight. I;

almost sound. 0). l'otnl (0 to 10) of the score was calculated for each group of 5 chicks.

(a): Infected case. (b): Uninleetetl ease methyl--(2-methylsulfinylethyl)thiazolium hydrochloride dihydrate (16.8 g) is added to a solution pound No. 1). These compounds have very low toxicity.

Presently-preferred and practical embodiments of the present invention are illustratively shown in the following examples.

EXAMPLE 1 under reduced pressure, and the residue is extractedwith n-butanol. The n-butanol layer is evaporated under reduced pressure, and the residue is crystallized from ether. The crystals are chromatographed on a column of alumina/ethanol to give bis- {2-[N-(2-methyl-4- aminopyrimidin-S-ylmethyl)formamido]-1-(2- methylsulfinylethyl)-l-propenyl} disulfide (2g) as colorless prisms melting at 168 to 170C (decomp.). UV: A 234 mp.(log e 4.41), 279 mp.(log e 4.04).

EXAMPLE 2 3-( 2-Methyl-4-aminopyrimidin-5-ylmethyl )-4- Chloride of sodium hydroxide (4.8 g) in water (40 ml) with ice cooling, and the mixture is stirred at C for minutes. A solution of potassium ferricynate (13.2 g) in water (70 ml) is added dropwise below 10C in 15 minutes thereto. The resultant mixture is adjusted to pH 11 1.5 with 10 percent aqueous sodium hydroxide solution and stirred at room temperature for 1.5 hours. The reaction mixture is extracted with n-butanol. The organic layer is washed with water, dried and evaporated under reduced pressure to give bis-{2-[N-(2-methyl-4- amino-pyrimidin-S-ylme.thyl)formamido]-1 (2- methylsulfinylethyl)-1-propenyl} disulfide (12.7 g). This substance is recrystallized from ethanol to give colorless prisms melting at 168 to 170C (decomp.).

EXAMPLE 3 3-(2-Methyl-4-aminopyrimidin-5-ylmethyl)-4- methyl-5-(Z-methylthioethyl)thiazolium chloride hydrochloride hydrate (1.16 g) is dissolved in a solution of sodium hydroxide (0.36 g) in water (6 ml) with ice cooling, and the solution is allowed to stand for half an hour. A solution of potassium ferricynate (0.988 g)-in water (4 ml) is added dropwise thereto, and the mixture is adjusted to pH 11.5 to 11.8 with 10 percent sodium hydroxide solution. The resultant mixture is kept at 15C for 1.5 hours with stirring, and the precipitate is filtered, washed with water and dried to give bis-{2- lN-(2-methyl-4-aminopyrimidin-S- ylmethyl)formamidol-l-(2-methyl-thioethyl)-lpropcnyl} disulfide hydrate (0.87 g). The crystals are recrystallized from aqueous ethanol to give colorless needles, which begin to melt at about 85C and complete melting at about 130C to give a yellowish white fused liquid. This hydrate is recrystallized from ethyl v acetate to give the anhydrous colorless prisms melting at 164 to 165C.

EXAMPLE 4 3-(2-Methyl-4-aminopyrimidin-S-ylmethyl)-4- methyl-5-(2-methylthioethyl)thiazolium chloride hydrochloride hydrate (1.16 g) is dissolved in a solution of sodium hydroxide (0.36 g) in water (6 ml) with ice cooling, and the solution is allowed to stand at room temperature for half an hour. A solution of iodine (0.38 g) and potassium iodide (0.9 g) in water (30 ml) is added dropwise in half an hour, and the resultant mixture is stirred for an hour. The precipitate is filtered, washed with water and dried to give bis-{2-[N(2- 'methyl-4-aminopyrimidin-5-ylmethyl)formamido]- l (2-methylthi0ethyl)-1-propenyl} disulfide hydrate (0.72 g). 1

EXAMPLE 5 3-(2-Methyl-4-am inopyrimidin-S-ylmethyl)-4- methyl-5-(2rmethylthio'ethyl)thiazolium chloride hydrochloride hydrate (1.16 g) is dissolved in a solution of sodium hydroxide (0.36 g) in water (6 ml) with ice cooling, and the solution is allowed to stand at room temperature for half an hour. A 30 percent hydrogen peroxide solution (0.68 g) is added dropwise thereto.

The resultant mixture is kept at pH 11.8 and stirred with ice cooling for 2 hours. The precipitate is filtered, washed with water and dried to give bis-{2-[N-(2- methyl-4-amino-pyrimidin-5-ylmethyl)formamido] -l- (2-methylthioethyl)-l-propenyl} disulfide hydrate (0.501 g).

EXAMPLE 6 3-(2-Methyl-4-aminopyrimidin-5-ylmethyl)-4- methyl-5-(2-methylsulfinylethyl)thiazolium chloride hydrochloride dihydrate (210 g) is dissolved in water (420 ml), and 10 percent aqueous sodium hydroxide solution (400 g) is added thereto. The resultant solution is heated at 50C, and kept at pH 7.1 with 10 percent aqueous sodium bicarbonate solution. The solution is allowed to stand at room temperature for 2 days. The precipitate is filtered. The said precipitate is recrystallized from aqueous ethanol and chromatographed on a column of silica gel to give bis-{2-[N-(2- methyl-4-aminopyrimidin-S-ylmethyl) formamido]-l- (2-methylthioethyl)-l-propenyl} disulfide (60.3 g) as crystals melting at 164 to 165C. The filtrate is shaken The powder is dissolved in 1,000 to 2,000 volumes of water before use.

EXAMPLE 8 Bis-{2-[N-(2-mcthyl-4-aminopyrimidin-5-ylmethyl)- formamido]-l-(2-methylthioethyl)-l-propenyl} disulfide 10 parts by weight) is admixed with rice bran parts by weight) to give a homogeneous mix. The mix is diluted with chicken feed to a concentration of 0.008 to 0.015 percent of the effective ingredient in the feed before use.

EXAMPLE 9 f 2 CH0 CH -C c-cn -rz s ii i: rr \C 'C/ 5- \CHZCHZ-R 2 wherein R represents an alkylthio group containing l to 4 carbon atoms or an alkylsulfinyl group containing 1 to 4 carbon atoms, or their pharmaceutically acceptable acid-addition salts.

2. A thiamine disulfide compound according to claim 1, in which R is methylthio.

3. A thiamine disulfide compound according to claim 1, in which R is methylsulfinyl.

l= =l =l 

1. THIAMINE DISULFIDE COMPOUNDS REPRESENTED BY THE FORMULA:
 2. A thiamine disulfide compound according to claim 1, in which R is methylthio.
 3. A thiamine disulfide compound according to claim 1, in which R is methylsulfinyl. 